A timeline is a device to make history easier to understand. At least, thatâ€™s the way itâ€™s supposed to work! This Wikipedia entry plots a timeline to explain the three Back to the Future movies. Now Iâ€™m more confused than when I watched them. Link

Good Time-Line picture, exist a mistake in timeline 5, in fact the timeline 5 should be removed because Doc, Marty and Jenniffer jump to Biff's timeline and from this timeline (4) Marty and Doc jump to timeline 6. However its a great picture congrats to the maker.